Narrative:

The potentially dangerous conflict involves a new railroad crossing gate system that activates when an aircraft or authorized vehicle uses taxiway 'victor.' victor and postmark drive intersect, and although victor is restricted to 'light' aircraft, it is heavily used especially in the summer by transient aircraft landing at Z41. For many yrs a simple stop sign stopped vehicle traffic which in turn gave way to aircraft on the taxiway. Both vehicles and aircraft used extreme caution. This past summer, the state installed a railroad gate/bar system which is activated by weight on sensors on the taxiway. The speed limit on postmark drive is 25 mph, and when the gates are up, cars routinely speed through the intersection. I have also observed cars speed up to beat an aircraft as the bars were lowering and go under/around bars to avoid waiting. The gates have failed to activate, and they have activated for no apparent reason. This day, a BE90 was taxiing, and the gates did not lower. I instruct all aircraft to use caution because the gates are not reliable, but I can't police that intersection. If nothing else, the state should put the stop signs back until the system is safe. Callback conversation with reporter revealed the following information: reporter advised that two additional events have occurred. One event was observed when a vehicle increased its speed to beat the descending arms, causing the aircraft to stop, even though the aircraft had the right of way. The other when the gate arm did not activate as an aircraft proceeded across the road. The reporter advised that the state of alaska installed the equipment. He believes FAA management has notified the state representative of the gate's intermittent functioning without apparent resolution.

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Original NASA ASRS Text

Title: ANC GC CONCERNED WITH TXWY 'V' AND POSTMARK DRIVE, INTERMITTENTLY ACTIVATING, NEWLY STATE INSTALLED RAILROAD GATE XING SENSORS, THAT CONNECTS ANC ARPT WITH Z41 ARPT.

Narrative: THE POTENTIALLY DANGEROUS CONFLICT INVOLVES A NEW RAILROAD XING GATE SYS THAT ACTIVATES WHEN AN ACFT OR AUTHORIZED VEHICLE USES TXWY 'VICTOR.' VICTOR AND POSTMARK DRIVE INTERSECT, AND ALTHOUGH VICTOR IS RESTRICTED TO 'LIGHT' ACFT, IT IS HEAVILY USED ESPECIALLY IN THE SUMMER BY TRANSIENT ACFT LNDG AT Z41. FOR MANY YRS A SIMPLE STOP SIGN STOPPED VEHICLE TFC WHICH IN TURN GAVE WAY TO ACFT ON THE TXWY. BOTH VEHICLES AND ACFT USED EXTREME CAUTION. THIS PAST SUMMER, THE STATE INSTALLED A RAILROAD GATE/BAR SYS WHICH IS ACTIVATED BY WT ON SENSORS ON THE TXWY. THE SPEED LIMIT ON POSTMARK DRIVE IS 25 MPH, AND WHEN THE GATES ARE UP, CARS ROUTINELY SPEED THROUGH THE INTXN. I HAVE ALSO OBSERVED CARS SPEED UP TO BEAT AN ACFT AS THE BARS WERE LOWERING AND GO UNDER/AROUND BARS TO AVOID WAITING. THE GATES HAVE FAILED TO ACTIVATE, AND THEY HAVE ACTIVATED FOR NO APPARENT REASON. THIS DAY, A BE90 WAS TAXIING, AND THE GATES DID NOT LOWER. I INSTRUCT ALL ACFT TO USE CAUTION BECAUSE THE GATES ARE NOT RELIABLE, BUT I CAN'T POLICE THAT INTXN. IF NOTHING ELSE, THE STATE SHOULD PUT THE STOP SIGNS BACK UNTIL THE SYS IS SAFE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR ADVISED THAT TWO ADDITIONAL EVENTS HAVE OCCURRED. ONE EVENT WAS OBSERVED WHEN A VEHICLE INCREASED ITS SPEED TO BEAT THE DSNDING ARMS, CAUSING THE ACFT TO STOP, EVEN THOUGH THE ACFT HAD THE RIGHT OF WAY. THE OTHER WHEN THE GATE ARM DID NOT ACTIVATE AS AN ACFT PROCEEDED ACROSS THE ROAD. THE RPTR ADVISED THAT THE STATE OF ALASKA INSTALLED THE EQUIP. HE BELIEVES FAA MGMNT HAS NOTIFIED THE STATE REPRESENTATIVE OF THE GATE'S INTERMITTENT FUNCTIONING WITHOUT APPARENT RESOLUTION.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.